My fire company (and all the surrounding ones) are volunteer fire companies that run primarily on donations from the community. (Yes, various government agencies contribute too, but the bulk of their support is from private donations). About 70% of the fire departments in the USA work that way. In fact, mine's having a fund drive right now, if you care to contribute a few shekels. (Can't wait for their summer Ox Roast either, REALLY good food with the proceeds going to the department.) And no, they don't ask if you made a contribution this year before responding to a call. They just show up with their equipment and deal with the emergency as fast as they can safely do so.
And in that respect they behave exactly like the local hospital emergency room, which, by law, can't turn you away. They respond quickly and deal with the immediate danger very quickly. (But unlike the ER they don't send you a ridiculously inflated bill afterwards.) Once they leave the extinguished fire, once the condition is "stabilized" you're on your own. They don't provide repairs of that fire damage. That's why smart people carry fire damage insurance. But that's not a "legal" requirement anywhere that I'm aware.